Scanning tunneling microscopy of surfactant-mediated epitaxy of Ge on Si(111): strain relief mechanisms and growth kinetics

The role of strain relief and kinetics in surfactant-mediated epitaxial growth of Ge on Si(111) was studied with scanning tunneling microscopy. For coverages of up to ≈ 20 ML the images reveal a variety of strain relief mechanisms which include trench formation and increasing surface roughness. Additionally, at 10 ML, the onset of a periodic surface undulation is observed which coincides with the injection of misfit dislocations at the Ge-Si interface. For coverages larger than 20 ML, the Ge epilayer grows as defect-free atomically-flat large terraces. © 1992.